1. Technical Field
The embodiments herein generally relate to wireless technologies, and, more particularly, to WiFi technologies.
2. Description of the Related Art
In IEEE standards 802.11a/b/g/n, more commonly known as WiFi, packets containing data, information, or connection requirements are transmitted and received by an access point (AP) and a station. The physical (PHY) layer is responsible for demodulating signals received over the air before passing data bits on to the Media Access Control (MAC) layer and for modulating data bits from the MAC to be transmitted over the air.
802.11n contains numerous enhancements to 802.11g to improve throughput. Moreover, there are many additional features to the MAC layer. 802.11n PHY layer uses the same architecture as 802.11g with some additional enhancements. Both 802.11g and 802.11n (as well as 802.11a) use Orthogonal Frequency Division Multiplexing (OFDM) as their modulation scheme. However, 802.11b PHY uses Direct-sequence spread spectrum (DSSS) and Complementary code keying (CCK) as its modulation technique. Accordingly, Wi-Fi PHY has two modes of operation: OFDM and single carrier.
However, the problem is the modulation/demodulation scheme for 802.11b and 802.11g are different and incompatible. Supporting both standards is necessary due to legacy reasons, however, including both PHYs is expensive in terms of area because the wireless transceiver chip is an application-specific integrated circuit (ASIC) which has limitations in die size. Moreover, both PHY cores need to work simultaneously in a WiFi receiver to detect the type of a packet. This causes a large die size. Therefore, it is desirable to develop a way to reduce the area overhead of supporting both 802.11b and 802.11g WiFi standards.